Tandavan, Doctor As we have suggested previously, the total fat or oil consumption in our diet should consist of no more than 30% of ingested calories. This is somewhat less than 3-4 teaspoons of added fat per day, as the balance is obtained from the foods we eat. Of this, no more than 50% should be saturated fats, which have been connected with degenerative disease. The balance should be mostly monounsaturated fats, since they are less likely to produce free radicals and are easily digested.
In order to prolong the shelf life of your chosen dietary oils, it is suggested that the contents of a capsule of Vitamin E, 200 units, be placed within the oil every two weeks until it is consumed. This will tend to prevent free radical formation and delay rancidity. Also all oils should be kept within the refrigerator in a tightly closed container, preferably opaque.
The highly advertised "Omega 3 marine lipids" (found in seafood) are said to help prevent heart attacks. Data for this recommendation was taken from a study among Eskimos. Their diet is high in marine lipids and the incidence of coronary disease is low; however, the stress level of their life style is not similar to ours. So there is some doubt about this study's value.
As vegetarians, we do not need to use marine sources as these lipids are found in wheat, flax seed, navy beans, kidney beans, red and pinto beans, chestnuts, walnuts and flax seed oil. This oil is very fragile and is best used in salads. Butter also contains a small amount of the Omega 3's. There does not have to be any supplementation to the diet in order to have a sufficient intake of Omega 3's.
Canola oil is from the rape-seed and has many ideal properties. This is a special hybrid plant with a low amount of the toxic erucic acid. Since the label does not tell us how much of this remains we probably would be better off not to use the oil. This oil is very low in saturated fat (6%) high in unsaturated fat (62%) and contains about 10% Omega 3 lipids. So you see, except for the erucic acid content, this is an ideal oil.
Safflower and sunflower seed oils are very high in polyunsaturated fats, so they are very prone to form free radicals. The shelf life may be 2-3 months, whereas extra virgin olive oil may last 9 months.
There are many ways that we can lower fat consumption. When sauteing, we can use less oil (e.g., 1 tablespoon instead of 3). Instead of sauteing onions and other vegetables, we may soften them in vegetable juices or broths; or they can be browned in a hot oven after spraying with a small amount of oil. This is a good way to prepare low fat "french fries." Deep frying should be eliminated. Heavy cream can be replaced by yogurt and skim milk fortified with milk solids. Yogurt is also a good substitute for sour cream. Delicious pop corn can be made by air popping or in the microwave with no fat. Flavors can be added that also contain little or no salt.
One may ask if it is advisable to totally eliminate all fat from the diet. This is not entirely possible. Some studies have been done with tribes that use no fat in cooking. Their caloric intake was less than 2% due to fats. They seemed to be in a state of health comparable to other neighboring tribes that had much higher levels of fat. But the vegetables, grains, seeds and nuts we do eat contain some fat so it is almost impossible to totally eliminate it. There is need for even saturated fats as a source of energy as well as the building blocks for other very essential substances for proper functioning of our bodies.
The amount of saturated fat can be reduced below the levels of 50%, but it should not exceed this amount. All recommendations about dietary fat are true for adults and children over the age of two years. Children less than two years old need a higher fat diet to develop normally. Their diet should consist of mother's milk and additions suggested by the pediatrician.